Robert de Vere, 3rd Earl of Oxford

Robert de Vere, 3rd Earl of Oxford (1170-1221) was Earl of Oxford from 1214 to 1221, succeeding Aubrey de Vere and preceding Hugh de Vere.

Biography
Robert de Vere was the son of Aubrey de Vere, 2nd Earl of Oxford, and he succeeded his father as Earl of Oxford and Master Chamberlain of England in 1214. In 1215, he joined the group of disaffected barons who forced King John of England to issue Magna Carta at Runnymede, leading to Pope Innocent III excommunicating him. He joined other nobles in offering the throne to Prince Louis of France, and he took up arms against King John. However, he joined King John after his capture of Castle Hedingham in 1216. Oxford then betrayed King John again, doing homage to Prince Louis at Rochester and assisting him with his entry into London and his capture of Winchester by year's end. In 1217, Prince Louis recaptured Castle Hedingham and restored it to the Earl of Oxford, but Oxford transferred his allegiance to King Henry III of England later that year. He was not fully restored to his lands and offices until 1218, and he served as king's justice from 1220 to 1221, when he died.